It wasn't meant to happen like this. The climate scientists told us that our winters would become wetter and our summers drier. So I can't claim that these floods were caused by climate change, or are even consistent with the models. But, like the ghost of Christmas yet to come, they offer us a glimpse of the possible winter world that we will inhabit if we don't sort ourselves out.

With rising sea levels and more winter rain - and remember that when the trees are dormant and the soils saturated, there are fewer places for the rain to go - all it will take is a freshwater flood to coincide with a high spring tide and we have a formula for full-blown disaster. We have now seen how localised floods can wipe out essential services and overwhelm emergency workers. But this month's events don't even register beside some of the predictions circulating in learned journals. Our primary political struggle must be to prevent the breakup of the Greenland and West Antarctic ice sheets. The only question now worth asking about climate change is how.

Dozens of new books seem to provide an answer: we can save the world by embracing "better, greener lifestyles". Last week, for instance, the Guardian published an extract from A Slice of Organic Life, the book by Sheherazade Goldsmith - married to the very rich environmentalist Zac - in which she teaches us "to live within nature's limits". It's easy. Just make your own bread, butter, cheese, jam, chutneys and pickles, keep a milking cow, a few pigs, goats, geese, ducks, chickens, beehives, gardens and orchards. Well, what are you waiting for?

Her book contains plenty of useful advice, and she comes across as modest, sincere and well-informed. But of lobbying for political change, there is not a word. You can save the planet from your own kitchen - if you have endless time and plenty of land. When I was reading it on the train, another passenger asked me if he could take a look. He flicked through it for a moment, and then summed up the problem in seven words: "This is for people who don't work."

The media's obsession with beauty, wealth and fame blights every issue it touches, but none more so than green politics. There is an inherent conflict between the aspirational lifestyle journalism that makes readers feel better about themselves and sells country kitchens, and the central demand of environmentalism - that we should consume less. "None of these changes represents a sacrifice," Goldsmith tells us. "Being more conscientious isn't about giving up things." But it is if, like her, you own more than one home when others have none. Uncomfortable as this is for both the media and its advertisers, giving things up is an essential component of going green. A section on ethical shopping in Goldsmith's book advises us to buy organic, buy seasonal, buy local, buy sustainable, buy recycled. But it says nothing about buying less.

Green consumerism is becoming a pox on the planet. If it merely swapped the damaging goods we buy for less damaging ones, I would champion it. But two parallel markets are developing - one for unethical products and one for ethical products, and the expansion of the second does little to hinder the growth of the first. I am now drowning in a tide of ecojunk. Over the past six months, our coat pegs have become clogged with organic cotton bags, which - filled with packets of ginseng tea and jojoba oil bath salts - are now the obligatory gift at every environmental event. I have several lifetimes' supply of ballpoint pens made with recycled paper and about half a dozen miniature solar chargers for gadgets that I do not possess.

Last week the Telegraph told its readers not to abandon the fight to save the planet. "There is still hope, and the middle classes, with their composters and eco-gadgets, will be leading the way." It made some helpful suggestions, such as a "hydrogen-powered model racing car", which, for £74.99, comes with a solar panel, an electrolyser and a fuel cell. God knows what rare metals and energy-intensive processes were used to manufacture it. In the name of environmental consciousness, we have simply created new opportunities for surplus capital.

Ethical shopping is in danger of becoming another signifier of social status. I have met people who have bought solar panels and wind turbines before they have insulated their lofts, partly because they love gadgets but partly, I suspect, because everyone can then see how conscientious and how rich they are. We are often told that buying such products encourages us to think more widely about environmental challenges, but it is just as likely to be depoliticising. Green consumerism is another form of atomisation - a substitute for collective action. No political challenge can be met by shopping.

The middle classes rebrand their lives, congratulate themselves on going green, and carry on buying and flying as much as before. It is easy to picture a situation in which the whole world religiously buys green products and its carbon emissions continue to soar.

As many environmentalists argue, it is true that most people find aspirational green living more attractive than dour puritanism. But it can also be alienating. I have met plenty of farm labourers and tenants who are desperate to start a farm of their own but have been excluded by what they call "horsiculture": small parcels of agricultural land that are being bought up for pony paddocks and hobby farms. In places such as Surrey and the New Forest, farmland is now fetching up to £30,000 an acre as City bonuses are used to buy organic lifestyles. When the new owners dress up as milkmaids and then tell the excluded how to make butter, they run the risk of turning environmentalism into the whim of the elite.

Challenge the new green consumerism and you become a prig and a party pooper, the spectre at the feast. Against the shiny new world of organic aspirations you are forced to raise drab and boringly equitable restraints: carbon rationing, contraction and convergence, tougher building regulations, coach lanes on motorways. No colour supplement will carry an article about that. No rock star could live comfortably within his carbon ration.

But these measures, and the long hard political battle that is needed to bring them about, are unfortunately required to prevent the catastrophe that the recent floods presage - rather than merely playing at being green. Only when these measures have been applied does green consumerism become a substitute for current spending, rather than a supplement to it. They are harder to sell, not least because they cannot be bought from mail order catalogues. Hard political choices will have to be made, and the economic elite and its spending habits must be challenged, rather than groomed and flattered. The multimillionaires who have embraced the green agenda might suddenly discover another urgent cause.